Screen for a riding mower



FIG. 1 is a right side view of a screen for a riding mower;

FIG. 2 is a left side view of a screen for a riding mower;

FIG. 3 is a rear view of a screen for a mower; and,

FIG. 4 is a top view of a riding lawn mower.

The broken line showing of the mower is for illustrative purposes only, and forms no part of the claimed design. 

The ornamental design for a screen for a riding mower, as shown. 